The present invention relates to the production of light by chemiluminescence and, more particularly, the use of specific fluorescent agents for this purpose.
The principle and the techniques for the production of chemiluminescent light are described in detail in U.S. Pat. No. 4,678,608 which is incorporated in the present description as a reference.
Chemiluminescence is produced by a reaction in the liquid phase of an activator such as hydrogen peroxide with a fluorescent agent and an oxalate. Optionally, other secondary compounds can be present. In general, they are also fluorescent agents, which modify the characteristics of the emitted light.
Until now, there existed no simple means to produce orange chemiluminescent light which is satisfactory for the users. The prior art mixed yellow and red chemiluminescent light producing solutions to yield an orange colored light. The major drawback of this approach was that the color was blotchy, especially in a narrow environment, e.g. in a chemiluminescent glow necklace. Additionally, the two solutions would sometimes decay at different rates, leading to a shift in coloration with time, e.g. to yellow or red.
U.S. Pat. No. 5,122,306, the contents of which are herein incorporated by reference, discloses a chemiluminescent solution based on substituted perylene for producing a red chemiluminescent light.
There exists a significant demand for orange chemiluminescent light. Orange is a color which is greatly appreciated by the public at large and the ability to produce a pleasing orange coloration via a chemiluminescent composition would be highly desirable.
It has now been observed unexpectedly that known fluorescent dyes which are soluble in organic solvents and, particularly, disubstituted perylene tetracarboxylic acids, their dianhydrides and diiimides, can be used advantageously to produce a chemiluminescent light, particularly an orange chemiluminescent light, which is particularly appreciated by the users and which differs from the colors produced in the prior art.
Accordingly, it is an objective of the instant invention to teach a composition adapted to be reacted with hydrogen peroxide to provide orange chemiluminescent light.
It is a further objective of the instant invention to teach a composition for providing chemiluminescent light wherein the fluorescer is selected from 1,7-disubstituted perylene-3,4,9,10-tetracarboxylic acids, their dianhydrides and diimides.
Other objects and advantages of this invention will become apparent from the following description taken in conjunction with the accompanying drawings wherein are set forth, by way of illustration and example, certain embodiments of this invention.
The present invention relates to a composition adapted to be reacted with hydrogen peroxide to provide chemiluminescent light, said composition containing a 1,7, disubstituted perylene-3,4,9,10-tetracarboxylic dianhydride compound having the general formula: 
wherein
L1, L2 independently of each other are 1,2-ethylene, 1,2-ethenylene or 1,2-ethynylene;
R1, R2 independently of each other are hydrogen or C1-C30-alkyl, whose carbon atom chain optionally is interrupted by at least one moiety selected from the group consisting of xe2x80x94Oxe2x80x94, xe2x80x94Sxe2x80x94, xe2x80x94NR3xe2x80x94, xe2x80x94COxe2x80x94 and xe2x80x94SO2xe2x80x94 and/or which is optionally substituted once by a moiety selected from the group consisting of xe2x80x94COOR3, xe2x80x94SO3R3, cyano or a 5- to 7-membered heterocyclic radical which is attached via a nitrogen atom and which optionally contains one additional nitrogen atom, oxygen atom or sulfur atom and which is optionally aromatic; or substituted one or two times by hydroxyl, C1-C5-alkoxy, C5-C8-cycloalkyl or aryl, R3 being hydrogen or C1-C6-alkyl, the amount of said compound being such as to provide visible light.
Specific embodiments include compositions wherein L1, L2 are identical and are 1,2-ethenylene or 1,2-ethynylene and R1, R2 independently of one another are hydrogen or C1-C18-alkyl which can be substituted by xe2x80x94COOR3, hydroxyl or cyano. Additionally, specific heterocyclic radicals are 4-morpholinyl, 1-pyrrolidinyl, 1-piperidyl or 4-piperidyl.
The above-mentioned compounds, their related tetracarboxylic acids, and the diimides of said acids are described in PCT/EP96/05525 filed Dec. 11, 1996, now WO 97/22608, published Jun. 26, 1997 and U.S. Pat. No. 6,063,181, issued May 16, 2000, the contents of which are herein incorporated by reference. These patents also describe the preparation of analog derivatives. The preferred compound is sold under the trade name LUMOGEN PINK ED2222, and is known to be useful as a fluorescent dye For producing a pink light reflecting surface when compounded into various polymers. It has now been discovered that LUMOGEN PINK ED2222 will emit a true orange light, e.g. 580-585 nm, when utilized as a fluorescer composition in chemiluminescent light producing solutions.
To produce chemiluminescent light, the compounds according to the present invention are used under the conditions already described in the literature, particularly in said U.S. Pat. No. 4,678,608. In general, one can use any known solvent or oxalate which can be used for the production of chemiluminescent light. The solvent can be an ester, aromatic derivatives or a chlorinated hydrocarbon. Preferably, phthalates are used, in particular dibutyl phthalate.
Oxalates, such as those described in U.S. Pat. Nos. 3,749,679 and 3,846,316, incorporated herein by reference, may be used to produce the chemical reaction to cause chemiluminescent light when mixed with the fluorescers described above, with bis (2,4,5-trichloro-6-carbopentoxylphenyl) oxalate being exemplary.
Substituted carbalkoxyphenyl oxalate are the preferred class of oxalates used herein the oxalate and perylene fluorescer each being used in sufficient quantity to cause chemiluminescent light, preferably in a 20-40:1 oxalate to fluorescer, molar ratio.
Useful catalysts are disclosed in U.S. Pat. No. 3,775,336, incorporated herein by reference, in concentrations disclosed therein, and usually in the solvent solution of the hydrogen peroxide.
The areas of application are well known and they include the production of useful objects, particularly signs, decorative objects, games and gadgets such as chemiluminescent necklaces, etc. In such articles, the chemiluminescent light is produced by mixing a solution of an activator, in general oxygenated water (hydrogen peroxide), with a solution which contains the derivatives of disubstituted perylene and an oxalate diester. The article consists of, in its passive state, two compartments between which a communicating link was established at the time of use, for example as described in French Pat. No. 87 11296, for the case of flexible luminescent tubes.